1. Field of the Invention
The present invention relates to a two-wheeled motor vehicle brake control method and system and in particular to the improvement of controllability with respect to rear wheel lifting.
2. Description of the Related Art
Conventionally, it has been well known that, in two-wheeled motor vehicles, the larger the ratio between the height of the center of gravity of the vehicle and the inter-axial distance between the front and rear wheels is, the easier it is for the phenomenon of so-called lifting of the rear wheel to occur. Additionally, various coping technologies have been proposed with respect to such rear wheel lifting. For example, in Japanese Patent No. 3,416,819, there is disclosed a technology that detects rear wheel lifting on the basis of various conditions such as vehicle deceleration and a drop in the velocity of the rear wheel and adjusts the brake force of the brake.
Further, as disclosed in JP-A-2002-29403, there is disclosed a technology that enables more rapid detection of rear wheel lifting on the basis of a pseudo vehicle body deceleration.
However, in the aforementioned technologies, although the techniques for determining rear wheel lifting are different, the times when lifting of the rear wheel is determined and a detection signal is obtained in both are basically after actual lifting of the rear wheel has occurred.
Additionally, control of brake force for controlling lifting of the rear wheel is executed after the determination result of rear wheel lifting and after a detection signal has been obtained, so there is the problem that a situation where a temporal delay to a certain extent basically cannot be avoided until the effect of control appears.
Related application serial No. 12/161,370, filed Jul. 18, 2008, currently pending; 12/162,223, filed Jul. 25, 2008, currently pending; 12/162,220, filed Jul. 25, 2008, currently pending; and 12/162,626, filed Jul. 30, 2008, currently pending, are directed to similar subject matter. The '370 application is directed to a two-wheeled motor vehicle brake control method and system which enables a more rapid and reliable securement of safety with respect to rear wheel lifting; the '223 application is directed to a two-wheeled motor vehicle brake control method and system that can reliably control and prevent rear wheel lifting caused by an abrupt brake operation; the '220 application is directed to a two-wheeled motor vehicle brake control method and system that can prevent a so-called no-brake state; and the '626 application is directed to a two-wheeled motor vehicle brake control method and system for securement of high safety with respect to rear wheel lifting by reducing a pressure increase gradient of a wheel cylinder pressure of the front wheel immediately after rear wheel lifting.